You'll gonna see the instructions on the autometer site:
Here for gauge cage on 87-93 mustang(Acrobat reader format)
Here for filled with liquid gauge Oil or temp (Acrobat reader format)
For keeping your factory gauge working you're better putting a 'Y' on your copper line at the base of the plug.
For now this is just technical. I didn't tried to install on mine but this is my plan soon.
Hope this help.
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88 GT, K&N, Home Made Ram Air, Convertible Engine Mount, Dynomax Super Turbo, 180° thermostat, Energy sway bar bushings, Strut tower brace.
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